LONDON — We all know a week is a long time in politics, but Westminster life at the end of this week could look more different than we could possibly imagine.

A few months ago Prime Minister David Cameron must have been looking forward to a growing advantage in the polls for a vote to Remain, with his biggest post-poll worry being the need to keep the look of smug vindication off his face as he put together his government of reconciliation.

But the belief that British conservatism and deference would obligingly vote for the status quo is looking less and less well founded. Nobody seems to know how reliable the polls are, and the whole thing is far too close for comfort for Cameron. We know he is not going to fight the next election, but I suspect that whatever his plans were for a dignified exit, they are undergoing constant modification.

The idea was that, with Britain's place in the EU secured for a generation, at a time of his choosing he would walk off the stage, reminding journalists of his record of winning three referendums and two general elections.

A couple of months ago, "Downing Street sources" were talking of Cameron staying put until at least 2018 and possibly 2019. That looked to me like expectation management, allowing Cameron to stay for a year or so, but also enabling him to slip away once he had maximized George Osborne's chances (and minimized Boris Johnson's) of succeeding him. It would also advertise that he was leaving when he chose to do so, the first prime minister in a position to make that claim for 40 years.

But the biggest spur to his leaving soon, I believe, is his wife Samantha, who has had more than enough of Downing Street's gilded cage, and that her children have never known a life unencumbered by round-the-clock security. She has pretty much put her own career on hold, and is well placed to make serious money as a fashion designer, but she has had enough of high office, and will know as well as her husband that power eventually sends the most equable of people round the twist.

For now, they remain a comparatively normal couple, but that time is finite. So, I reckon, the demands of family life and political vanity meant that he would go as soon as it was clear he wasn't being chased out by the Right.

Would he willingly vacate the top job while his likeliest successor was Johnson, who in the final analysis he regards as an irresponsible clown?

Events, however, have intervened. Cameron has said he will stay on as prime minister if the Brexiteers win, to preside over the negotiation of Britain's deal outside the EU.

Knowing voices have ignored this, saying the PM has to say that but it is unrealistic, and certainly the political textbooks will tell you the blow to his authority (the controversial calling of the referendum, the rejection of his Brussels deal) would be fatal.

The sight of triumphant Brexiteers, fuming at what they see as Cameron's high-handedness, may force the issue and gather the 50 signatures needed to force a vote of confidence in his leadership.

But there are reasons why he might stay, including that the most senior colleagues who want to Leave the EU say they wouldn't want him to leave Downing Street, not yet anyway, not least because the already feverish financial markets would go into overdrive.

And there is a good chance Cameron would want to hold on.

Whatever his other motives, he feels a sense of public duty very strongly. Would such a person really want to walk away, leaving the country rudderless and the Tory Party torn and in need of a new leader? The lessons of William Hague's and Michael Howard's departures — with which Cameron will be intimately familiar — is that the Tories make the wrong choice if rushed into it (he having been the "right" choice, post-Howard).

Some say he might stay but only until this autumn's party conference, and that is probably the safest bet in the event of a Brexit, but that brings us to another reason he might want to hang on: Boris Johnson. Would he willingly vacate the top job while his likeliest successor was Johnson, who in the final analysis he regards as an irresponsible clown?

Dave the butler

Staying on to "mind the shop" would chime with a narrative that sees Cameron as butler to the nation, telling the electorate "very well, I shall attend to it" and setting about translating a pro-Brexit vote into a series of deals and treaties to see us through the choppy waters.

He could not decently leave such a task for a couple of years, but would win brownie points for sound husbandry and statesmanship. He could conceivably even call an election to seek a personal mandate. And the danger to the U.K. that a Brexit win would present would surely get his juices going. In those circumstances, his family might have to wait a little longer. the call of duty might be too strong.

But if the Remain camp wins, we have a paradox. Unless the victory is extremely slim, Cameron would be entitled to claim vindication. His vision of keeping things as they are would be safe for a bit longer. His job would be done.

He could talk magnanimously of the need to move on, of the need to put the Tory Party back together again. Come back, Michael Gove. Hard lines, Liam Fox — you fought a clean fight, have a peerage and a job. Boris, pull up a ministry (although not one that matches your ambition). And there the maestro leaves us (whether wanting more or not is for the reader to decide), his greatest "essay crisis" seen off.

So if you are one of those curious people who thinks personalities are all that matters, and that the most important thing is to get rid of David Cameron as soon as possible, it is just possible you'll get him out quickest by voting Remain on Thursday.

James Hanning is co-author, with Francis Elliott, of "David Cameron: Practically a Conservative."

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Tom Cullem

Please – if the man had a strong sense of public duty, he would have told his backbenchers to stuff it and risk UKIP getting a few more votes, and never offered the referendum in the first place, but let the EU unravel eventually under the weight of its own sclerotic bureaucracy and let growing revolt in Europe do the heavy lifting. But for a short-term gain, he handed a loaded revolve to the electorate and is shocked, SHOCKED! to find that they actually may pull the trigger!

He has made more u-turns and climb-downs than one can count. He has bawled defiance and then done what Merkel and Brussels want him to. He has looked out for the 1% and shafted the rest. If REMAIN win, look for that “Migration Impact Fund” to evaporate as so much else did (“no ifs, no buts”), and when the EU unrolls their proposals for mandatory migrant quotas and huge fines for those not taken as assigned, he’ll do some more defiant bawling and then do what Merkel and Brussels tell him to, as he doesn’t have to worry about a referendum OR re-election.